21210010100 has 36 divisors (see below), whose sum is σ = 46481444268. Its totient is φ = 8400000000.

The previous prime is 21210010097. The next prime is 21210010177. The reversal of 21210010100 is 101001212.

It can be written as a sum of positive squares in 6 ways, for example, as 5421082384 + 15788927716 = 73628^2 + 125654^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1039901 + ... + 1060100.

Almost surely, 2^21210010100 is an apocalyptic number.

21210010100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210010100 is an abundant number, since it is smaller than the sum of its proper divisors (25271434168).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21210010100 is a wasteful number, since it uses less digits than its factorization.

21210010100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100116 (or 2100109 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21210010100 its reverse (101001212), we get a palindrome (21311011312).

The spelling of 21210010100 in words is "twenty-one billion, two hundred ten million, ten thousand, one hundred".